Canon EF-S 24 / 2.8 STM is a pancake lens that is a crop analog of a full-frame Canon EF 40 / 2.8 STM... The body is made of matte black plastic typical of this manufacturer's lenses. The white point indicates the orientation of the lens required for docking with the camera. The controls include an autofocus switch and a focusing ring on the nose of the lens. Aperture control is carried out through the camera menu.  Unlike most EF-S lenses, this one is not compatible with full-frame cameras not only “mechanically” due to the artificially added plastic part catching the mirror. The rear focal segment of the lens really does not allow achieving focus at infinity when trying to mount it on a camera with an EF mount. View of the rear lens protruding beyond the bayonet plane On the back of the Canon EF-S 24 / 2.8 STM, you can see the words “Made in Malaysia” next to the mount contacts. The inscription indicating the country of manufacture on the back of the lens The lens focuses with the movement of the entire lens block. At the same time, its front part remains motionless and does not play. The drive is a gear stepper motor (STM), the main advantage of which is a fast, silent and smooth focusing when shooting movies, as the manufacturer claims. In reality, it requires a camera that supports the charms and autofocus chips with STM lenses (Canon 650D, 100D, 250D - for example): mine Canon 600D it doesn’t work with them and in the video it focuses in auto mode very badly. On the other hand, the focus is really not noisy - a noticeable buzzing appears only with a quick full run of lenses. Occasionally, you can hear soft jerky sounds when the motor produces an accurate fine-tuning of focus. Infinity Focus Lens Lens view when focusing on MDF In the photo mode, autofocus works very quickly and tenaciously even on my camera, the time for a lens to completely run from MDF to infinity is less than a second. At medium distances, focusing from infinity is almost instantaneous - the lens allows you to shoot live dynamic scenes and is very convenient for shooting, for example, indoor events. The maneuverability of the bundle of a rather small crop camera with the tiny Canon EF-S 24 / 2.8 STM helps in this. Unfortunately, focusing is only available when the camera is on - even if you use the manual focus mode. In other words, there is no direct connection between the ring and the focusing mechanism: this is due to the characteristic manner of manual focusing of the lens, which requires habit after old lenses. And thanks to this, the ring does not rotate during automatic focusing and is always available for manual correction. The aperture of the lens consists of 7 petals, and the shape of the hole is always very close to round. A trifle, and so nice! Point light sources will give a bun of 14 rays with a closed aperture. View of the lens diaphragm through the rear lens Canon EF-S 24 / 2.8 STM almost perfect round aperture. Canon EF-S 24 / 2.8 STM almost perfect round aperture. To take a photo of the lens with a covered aperture, I needed to attach it to the camera, select the aperture value and press the button next to the mount, closing the aperture to the selected value. Holding this button, I disconnected the lens. When I did this in Live View, the camera went a little crazy and had to reboot it with a battery. Do not do so. Half a century of difference: Helios-44 and Canon EF-S 24 / 2.8 STM. The Canon EF-S 24 / 2.8 STM turned out to be a well-built and very easy-to-use lens. I could not find any obvious flaws in the design or operation of the automation. If you find fault, then a drawback can be called a feature of the STM-drive associated with the inability to focus the lens on the camera off. Optical propertiesOn Canon crop cameras, the EF-S 24 / 2.8 STM is a moderate wide or, rather, a universal staffer, with EGF 38 mm. Unlike full-frame 24mm lenses, the Canon EF-S 24/2.8 STM has a much less asymmetric optical design, which reduces field aberrations. In addition, the correction of optical distortion provides an aspherical rear element. The picture on the lens is very sharp with an open aperture. Only in the corners of the frame can you notice a small (in comparison with any ancient wide-angle manuals so precisely) coma. There is a noticeable vignetting (up to 50%), its indirect sign is the twisting of the lens bokeh on the open aperture. When changing the aperture to F / 4.5, the lens becomes very sharp, aberrations disappear. Further closing of the diaphragm leads to an increase in the depth of the sharply depicted space. Changing the picture when aperture: Canon EF-S 24 / 2.8 STM. Canon EF-S 24 / 2.8 STM. Canon EF-S 24 / 2.8 STM. Canon EF-S 24 / 2.8 STM copes very well with backlight: only bright sunshine directly in the forehead can make the frame fill with hares. Lens behavior in hard backlight The lens has very good color reproduction, excellent image contrast. For correction of residual aberrations (mainly vignetting and slight barrel distortion), a profile is available in Canon DPP. At apertures close to F / 2.8 and small focusing distances, the Canon EF-S 24 / 2.8 STM shows a pleasant blurring of the background. At portrait distances, the object is weakly separated from the background. The short focusing distance (only 16 cm) allows you to shoot close-up objects, while interesting promising distortions become quite noticeable. It is quite difficult to pronounce such a phrase, but it seems to me that this lens has no drawbacks related to the optical part: the open aperture is fully operational, to achieve maximum resolution it is enough to cover the aperture with a stop and a half. Sample photos on the Canon EF-S 24 / 2.8 STM and Canon 600D (development from RAW to Canon DPP, correction profile applied selectively) are shown below. ConclusionsCanon EF-S 24 / 2.8 STM is a very, very successful lens for APS-C format SLR cameras. Compact, fast, high quality and affordable. There are no significant flaws. Holy Grail for crop camera owners. |
